Conventional separate networks of this type, for example, include three-phase networks with synchronous generators. The real power is distributed via the rotation-speed frequency droop of the rotation-speed regulators for the diesel engines or turbine drives. The reactive load is distributed via the voltage droop of the generator voltage regulator. Droop devices as well as load sharing when two generators are operated in parallel, are described in the technical information document ASI NMA/TNG3 from Siemens AG, entitled "THYRIPART-Erregung in burstenlosen Siemens-Synchrongeneratoren" [THYRIPART Excitation in Brushless Siemens Synchronous Generators] by Joachim Frauenhofer. The entire contents of this document are hereby included and are presupposed for the following statements.
In three-phase separate networks, it is conventional for an additional voltage value to be generated for load sharing of parallel-operating generators, from the output current of the generator, for the nominal/actual value comparison input of a voltage regulator. The additional voltage value allows the generator voltage to be reduced in proportion to the rising reactive current. However, this is dependent on the capability to influence the generator voltage externally from a separate functional component. Such DC generators or AC generators whose voltage can be controlled or regulated, have the disadvantages, however, that they are physically voluminous, heavy and costly to manufacture. Furthermore, there is a considerable requirement for intrinsically autonomous energy generation and power supply separate networks which are distinguished by being physically small and compact as well as being light in weight, particularly with regard to electricity generators.
U.S. Pat. No. 5,200,643 describes a power supply network that has a plurality of DC supply sources, which feed into amplifiers that have control inputs. Signals for the output actual voltage and the output actual current are combined with a reference signal. The aim in this case is to provide a signal for the control error, with the output voltage of each source being regulated.
U.S. Pat. No. 5,334,436 describes a fuel battery. However, when a plurality of sources are paralleled without any higher-level regulating device it is impossible to achieve sufficiently good and desirable load sharing or to ensure satisfactory network stability.
In order to overcome the disadvantages resulting from the above-mentioned patents, and to solve the equivalent problems, the present invention proposes an energy generation system, a power supply network, and a control loop.